Boxable drywall corner bead

ABSTRACT

A boxable corner bead for finishing drywall corners that is made from two flanges with a protruding nose section. This bead can be made in regular, bullnose, or flex trim type arrangements. Once the bead is attached to a drywall corner, it can be mudded on both sides of the corner without waiting for the mud on the first side to dry. This is because of the shape of the nose which allows a mud dispensing box to apply mud on one side without getting mud on the nose. The box can then be immediately moved to the other side, where that side can be mudded. The nose itself is prepared to directly receive paint or texture, and hence does not need any mud. The flex-trim version has a raised trapezoidal section with a V-groove cut in the back. The bead hinges around the V-groove to match any corner angle. Both sides can be mudded as with the fixed bead. The beads can be used with both interior and exterior corners.

This is a continuation of co-pending application Ser. No. 09/965,641filed Sep. 27, 2001 which was a continuation-in-part of application Ser.No. 09/608,084 filed Jun. 30, 2000, now abandoned.

BACKGROUND

1. Field of the Invention

This invention relates generally to the field drywall construction andmore particularly to a drywall corner bead that can be finished on bothsides wet with a standard mud dispensing box typical in the trade.

2. Description of the Related Art

For years in the drywall trade, automatic taping tool companies havetried to come up with a tool to box corners in one step. Boxing a cornermeans putting drywall mud on both sides of it in a condition that canlater be sanded and painted. The problem with boxing traditional cornersis that only one side at a time can be tooled. If an attempt is made totool both sides of a corner at the same time, either the guide on themud dispensing box will disturb (and ruin) the mud on the other side ofthe corner, or the mud coming out of the box will flow onto the otherside. In either case, the corner would be left in an unacceptablecondition. This has forced tooling or boxing only one side of eachcorner at a time. One side is tooled, then the mud must be allowed todry, a process that requires coming back at least a day later. Onlyafter the mud on the first side is totally dry, can the second side betooled. Workers must typically pass through a construction site toolingonly first sides of corners. They must then come back on a subsequentday to tool the second sides. This puts at least an extra day into theconstruction cycle.

What is badly needed it a corner bead that will allow a standard muddispensing box to tool both sides of a corner while the mud is stillwet. This corner should be available in standard or bullnose (rounded)styles for exterior corners, and should be a available as a flex-trimfor interior corners. The worker should be able to mud one side andimmediately mud the other.

SUMMARY OF THE INVENTION

The present invention relates to a drywall corner bead that can bemudded on both sides while the mud is still wet. At the apex of thebead, there is a flat finished surface that is prepared to receive paintor texture. This apex is shaped so that a standard mud dispensing boxcan deposit mud down one side without the mud running up entirely to theapex. Thus a finished side can be mudded without any mud on the apex.This then allows the box to mud the second side without any interferenceto the first side.

The bead resembles a standard corner bead with two flanges. The flangescan be flat or can taper or be beveled. The flanges can be nailed,glued, or mudded onto the wallboard. At the apex is the finished surfacethat never needs mud. The surface of the apex can be finished in any waythat will allow it to take paint or texture. It can be roughed slightly,or it can be coated by a material to which paint or texture will adhere.The bead can be made from any plastic, high impact plastic, metal, orany other rigid material.

In the process, the worker cuts the bead to length and attaches it tothe corner by any method (nailing, gluing, or mudding), and then mudsthe first side with a standard box. At typical box is seven inches.Immediately after mud is applied to the first side, the worker can moveto the second side and mud it in an identical manner. The corner is thustotally mudded in minutes without any drying wait period. The boxablebead can be supplied in regular or bullnose styles for exterior corners,and interior trim or flex-trim for interior corners. It can come instandard lengths, or for trim, optionally in rolls.

The shape of the apex or nose on both the exterior and interior beads isthe key to the ability of the present invention to function and totallydistinguishes the present invention from the prior art. This uniqueshape allows the mud box to dispense mud on one side without the mudslopping over to the other side. This shape also allows a specialtwo-part mud box to be designed that can dispense mud on both sidessimultaneously.

Prior art corner beads with any shape of nose would allow mud to slopover when being applied to one side. In all prior art systems, mud mustbe applied to one side and then allowed to dry before new wet mud can beapplied to the other side.

The special shape feature of all the apexes of the present invention isa wide flat area coming off the tip followed by a quick drop-off intothe region designed to be mudded on each side. This flat area appears ona pointed apex for a sharp corner, a bullnose apex for a rounded corneror a sharp interior corner. Other shapes simply will not work.

On the exterior trim piece, an elongated protruding nose member isattached to a pair of flanges along the centerline on the room facingside. The protruding nose member has an elongated tip running parallelto the centerline end-to-end. The tip is formed by a pair of flatsurfaces meeting at an angle where each of the surfaces is approximatelyparallel to one of the flanges respectively. The flat surfaces extendaway from the elongated tip a predetermined distance to a taper pointwhere they end, and the nose member quickly tapers into the flangesbeyond the taper point. This way the elongated protruding nose memberprevents wet mud applied to one of the flanges from crossing over to theother of the flanges. The actual tip can be pointed for a square corneror rounded (arcuate) for a bullnose corner.

On the interior trim piece, the flanges are initially laid out flat(unfolded). An elongated trapezoidal nose member is attached to theflanges along the centerline on the room facing side and runs parallelto the centerline. The nose member has a flat top also parallel to theflanges which extends away from the centerline for a predetermineddistance to a taper point. Beyond the taper point, the flat top ends,and the nose member quickly tapers into the flanges. An elongated grooveruns end-to-end along the centerline on the wall facing side of theflanges. The groove penetrates into the nose member forming a hinge thatallows the flanges and the nose member to bend along the hinge to forman acute angle on the room facing side. The flat top on the nose membernow forms two sections (after folding to match the wall angle), eachsection is still approximately parallel to one of the flanges. Thesections form an acute angle on the room facing side such that the twosections on the nose member prevent wet mud applied to one of theflanges from crossing over to the other of the flanges.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this invention, reference shouldnow be made to the embodiments illustrated in greater detail in theaccompanying drawings and described below by way of examples of theinvention.

FIG. 1 shows a perspective view of the boxable bead with a standardstyle apex.

FIG. 2 shows a section of the corner and bead showing how the box isused to mud the bead.

FIG. 3 is the same as FIG. 2, except the bead is bullnose.

FIG. 4A shows the cross section of a trim type boxable bead for interiorcorners.

FIG. 4B shows a section of wall and corner for an interior corner thatis not 90 degrees using a flex type of boxable bead.

DESCRIPTION OF THE INVENTION

Turning to FIG. 1, a length of the boxable bead can be seen. This beadhas flanges 1 like any conventional bead. However, it can be clearlyseen that the nose 14 with apex 2 is different than a normal bead. Thisnose member 14 protrudes and runs end-to-end tapered into the flanges toallow a box to mud one side without interfering with the other. Thestyle of corner shown in FIG. 1 is an exterior standard corner. It isalso possible to construct the boxable bead of the present invention inbullnose or any other style. The nose 14 is finished or prepared todirectly receive paint or texture. This preparation can be a slightlyroughed surface, or a coating of any suitable material that paint ortexture will adhere to. If the structure is a laminate containing anouter paper layer, the paper can be of a type that can directly receivepaint or texture, or it can be prepared to receive paint or texture witha suitable coating. The entire surface of the bead could optionally bebonded with paper that can directly receive paint or texture.

The boxable bead of the present invention can be made of standardplastic, high impact polystyrene or other high impact plastic, metal, orany other rigid material. The preferred material is a high impactplastic. The structure can be a homogeneous piece, or it can be alaminate. While any type of laminate is within the scope of the presentinvention, preferred laminates are paper-plastic or paper-plastic-paper.The flanges 1 can optionally contain holes 13 to help the flange adhereto the drywall. It is also possible to rough the back side of theflanges or cause them to have ridges to make them adhere better. Holes,roughing, or ridges are used in the case when the bead is attached tothe wallboard with mud rather than glue or nails. Attaching with mud isthe preferred method.

FIG. 2 shows a section of wall, wallboard, and the boxable bead of thepresent invention installed on a 90 degree exterior corner. Drywallsheets 4 are nailed or screwed to wood 5 to form an exterior corner. Theboxable corner is attached to the corner with a flange 1 on each side ofthe corner as normal beads are installed. The boxable bead can be nailedon, glued, or mudded in place, or attached to the corner by any othermeans. A mud dispensing box 6 with a slot 7 for dispensing mud isbrought into contact with one side of the bead and wall as shown in FIG.2. The box is held by a worker by means of a handle 11. The sides of theapex of the bead 2 hold the box at the correct angle for dispensing asmooth layer of mud. No mud is placed on the actual center of the corner8. The corner shown in FIG. 2 is a standard corner. A layer of mud 3 isdispensed on the first corner, and immediately the box can begin muddingthe second corner as shown in FIG. 2.

The unique structure of the protruding nose can be seen in FIG. 2. Oneach side of the tip 8 a flat region 2 extends away from the tip 8 to ataper point and a region 15 where the nose structure quickly andabruptly drops into the flange 1 creating a deep well that prevents mudfrom one flange from slopping over onto the other flange.

FIG. 3 shows the same operation as FIG. 2 except the corner is bullnose9. In FIG. 3, no mud has yet been applied, where in FIG. 2, mud 3 hasbeen applied to one side of the bead. The bullnose apex 9 has a smallflat region 2 which the box 6 touches during dispensing of mud. Theactual apex 9 (and in FIG. 2 8) is prepared to directly receive paintand texture as previously described.

Again the unique structure of the protruding nose can be seen. In FIG. 3there is a rounded tip 9 with a flat region 2 extending away from thetip 9. The flat region 2 is approximately parallel to the surface of theflange 1. At a taper point, a region is entered 15 where the structurequickly and abruptly drops into the flange 1 creating a well thatprevents mud from one flange from slopping over onto the other flangeduring wet mudding of both sides of the structure.

FIG. 4A shows the cross section of a flex embodiment of the presentinvention. This can be used on both interior and exterior corners. Againthere is an elongated flat flange 1 with a notch or groove 12 on theback side. An apex 10 is shaped to form a perfect corner when a boxapplies mud. This is done by causing it to be a raised trapezoid sectionwith a long side and a short side. A V-groove 12 is cut in the longside. The piece hinges on the V-groove 12 to match any corner angle. Foran interior corner, a flat box may be used to mud the corner.

The structure of the trapezoidal nose can be clearly seen in FIG. 4A. Inthe unfolded configuration, the top of the trapezoid 10 is flat andparallel to the flange 1. At a taper point, a region of the nosestructure is reached 15 that quickly and abruptly drops to the flangesurface 1.

FIG. 4B shows the trim piece of FIG. 4A installed on a non-ninety degreeinterior corner. Studs 11 have sheets of wallboard 4 nailed or screwedin place. The flanges 1 of the corner of FIG. 4A is attached to thewallboard 4 by nailing, gluing, mudding, or by any attachment method.The flex piece opens along the slot or V-groove 12 to match the angle ofthe corner. It is possible to match any interior or exterior angle witha single designed piece. A flat mud box 6 with a mud dispensing slot 7and a handle 11 is again used to mud first one side of the corner 3 andthen the second side. Again the apex 10 of the corner is finished andprepared to directly receive paint or texture as previous described.

Here in the folded configuration, the flat top 10 of the trapezoiddivides into two parts each still parallel with the flange surface 1.Again, after a taper point, the structure drops abruptly 15 to theflange surface 1. This creates a steep wall that prevents mud from oneflange from slopping over to the other side.

The present invention saves considerable time in the drywall finishingprocess by allowing a worker to cut a corner to length, attach it, andthen box first one side and then immediately box the other side. As soonas the wall is dry, it can be sanded and a possible finish coat of mudcan be put on both sides to make up for shrinkage. In any case, it isnever necessary to wait for the first side to dry before beginning toapply mud with a box to the second side. It is possible to apply mud(box) both sides at the same time with a properly designed double box.

It should be noted that the above mentioned embodiments and descriptionsare only examples of the present invention. Many other configurations,materials, and methods are within the scope of the present invention.

1-13. (cancelled).
 14. A boxable drywall corner bead comprising: a pairof elongated flanges each with a wall facing side and a room facingside, said flanges joined side-to-side lengthwise along a centerlineforming an angle between said wall facing sides; an elongated centermember attached to each of said flanges along said centerline, saidcenter member running approximately parallel with said centerline havingrespective surfaces on each side of said centerline, said surfacespreventing wet mud cross-over from one of said flanges to the other ofsaid flanges during wet mudding of either of said flanges.
 15. Theboxable drywall corner bead of claim 14 wherein said flanges containmetal.
 16. The boxable drywall corner bead of claim 14 wherein saidelongated nose member contains metal.
 17. The boxable drywall cornerbead of claim 14 wherein said flanges are tapered.
 18. A boxable drywallcorner piece comprising: a pair of folding elongated flanges each hingedalong a centerline to a centerpiece strip, said center piece striphaving a room-facing surface prepared to directly receive paint ortexture and at least one back-facing surface, said centerpiece acting asa barrier to mud-crossover when said flanges are folded to a positionmatching a drywall corner; a single backing layer covering both of saidflanges and the back-facing surface of said centerpiece, said backinglayer being at least as wide as said flanges.
 19. The boxable drywallcorner piece of claim 18 wherein said backing layer is paper.
 20. Theboxable drywall corner piece of claim 18 wherein said elongated flangesare plastic.
 21. The boxable drywall corner piece of claim 18 whereinsaid centerpiece is plastic.